1. Field of the Invention
This invention is related to systems that simulate ambulatory propulsion of objects on leg-like motive structures and, more specifically, to leg-like structures and associated drive systems that produce uniform rectilinear motion of such leg-like motive structures to propel objects in a stable and controllable manner over a support surface.
2. Brief Description of the Prior Art
There have been many attempts to make leg-like mechanical systems for propelling objects ranging from robotic vehicles to toy bugs, and some of them are capable of performing that function. However, problems persist in achieving stable devices with minimum complexity in the mechanical and control systems. For example, many of the prior art leg-like mechanical structures, especially non-articulated and simpler articulated leg-like mechanical structures, impart some amount of bobbing (up and down) motion and/or weaving (side to side) motion and/or surging (forward accelerating and decelerating) motion to the object they are propelling with each step. Some of such bobbing, weaving, and surging motion may be tolerable at low speeds and some can be minimized or even removed with more complex articulated mechanical leg structures that incorporate electronic or other independent articulation control features. However, for simpler, articulated and unarticulated mechanical leg structures, any one or all of such bobbing, weaving, and surging motions become impulses that can cause chattering, loss of traction, and loss of control, even to the extent of knocking the object off balance, off track, and/or off the floor, ground, or other supporting surface or even tipping it over. Such bobbing and weaving can also dissipate energy, thereby reducing efficiency, and inefficient slippage of the legs on the supporting surface is also a problem, especially for systems in which the leg-like structures move at varying speeds in relation to the object and support surface during a step cycle. It may be possible to mitigate these problems with complex and intricate control systems articulated leg structures, but simpler and less expensive solutions are preferable.